1. Field of the Invention
This invention relates to an input device for instructing a desired function by moving an index to and aligning it with an icon indicating a printing function on a display screen without inputting characters from a keyboard when printing output, for example, is instructed to a computer.
2. Background Art
A conventional pointing device is such as shown in FIGS. 3 and 4. Shown in FIG. 3 is a pointing device 80 called "mouse" which contains a ball 81 which can rotate in any direction to move an index in all 2-D directions and which is provided with a sensor 82 for detecting the rotational direction and amount of the ball 81 with a magnetic or optical means.
To move the index displayed on a display screen of a computer (not shown), the ball 81 is rotated by moving the pointing device 80 on a flat surface such as the surface of a desk and the sensor 82 which has detected the rotation of the all 81 generates signals corresponding to the rotational direction and amount. Based on the signals, the index displayed on the display screen of the computer is moved to a targeted location.
A pointing deice 90 shown in FIG. 4 is such that two substrates 91 each of which consists of two electrodes 92 laid parallel to each other and a resistor film 93 having a predetermined resistance characteristic and formed between the electrodes 92 are placed one upon the other in such a manner that they cross each other at a right angle and have appropriate spacing between the resistor films 93 thereof.
Since one of the substrates 91 is made from an appropriate flexible member such as a resin film, when a finger is placed on the surface of the pointing device 90 at an arbitrary point and moved to an arbitrary direction, for example, from point P3 to point P4 in the figure, the resistor films 93 contact each other at locations on which the finger is placed sequentially and a predetermined resistance change occurs. This resistance change is calculated by an arithmetic circuit 95, for example, to obtain a moving direction, whereby the index displayed on the display screen of the computer is moved in that calculated direction.
However, in the above-described conventional pointing devices 80 and 90, when the index is to be moved, for example, from an end to an end of the display screen, it must be moved a long distance. A wide area is required on the surface of a desk in the pointing device 80 shown in FIG. 3, or the substrate 91 becomes large in size in the pointing device 90 shown in FIG. 4, resulting in a bulky pointing device.
When the above-described pointing device 80 is operated on a narrow surface of a desk or the pointing device 90 is reduced in size, in order to move the above index a long distance, the pointing device 80 must be moved over the surface of the desk a number of times or the pointing device 90 requires a finger to be placed and moved over the surface of the operation plane a number of times, thus complicating the operation.
When the moving amount of the index over the display screen with respect to the moving amount of the pointing device 80 or the moving amount of the finger over the surface of the pointing device 90 is increased to solve the above problems, operation within a narrow range is possible, but the movement of the index becomes rough, thereby making it difficult to move the index to a targeted location. Solutions to these problems have been awaited.